Moist multi-scale models for the hurricane embryo

2010 ◽  
Vol 657 ◽  
pp. 478-501 ◽  
Author(s):  
ANDREW J. MAJDA ◽  
YULONG XING ◽  
MAJID MOHAMMADIAN
Keyword(s):  
Applied Mathematics ◽  
Deep Convection ◽  
Asymptotic Methods ◽  
Finite Amplitude ◽  
Vertical Shear ◽  
Tropical Cyclogenesis ◽  
Heat Sources ◽  
Multi Scale ◽  
Scale Models ◽  
Anelastic Equations

Determining the finite-amplitude preconditioned states in the hurricane embryo, which lead to tropical cyclogenesis, is a central issue in contemporary meteorology. In the embryo there is competition between different preconditioning mechanisms involving hydrodynamics and moist thermodynamics, which can lead to cyclogenesis. Here systematic asymptotic methods from applied mathematics are utilized to develop new simplified moist multi-scale models starting from the moist anelastic equations. Three interesting multi-scale models emerge in the analysis. The balanced mesoscale vortex (BMV) dynamics and the microscale balanced hot tower (BHT) dynamics involve simplified balanced equations without gravity waves for vertical vorticity amplification due to moist heat sources and incorporate nonlinear advective fluxes across scales. The BMV model is the central one for tropical cyclogenesis in the embryo. The moist mesoscale wave (MMW) dynamics involves simplified equations for mesoscale moisture fluctuations, as well as linear hydrostatic waves driven by heat sources from moisture and eddy flux divergences. A simplified cloud physics model for deep convection is introduced here and used to study moist axisymmetric plumes in the BHT model. A simple application in periodic geometry involving the effects of mesoscale vertical shear and moist microscale hot towers on vortex amplification is developed here to illustrate features of the coupled multi-scale models. These results illustrate the use of these models in isolating key mechanisms in the embryo in a simplified content.

A First Look at the Structure of the Wave Pouch during the 2009 PREDICT–GRIP Dry Runs over the Atlantic

2012 ◽  
Vol 140 (4) ◽  
pp. 1144-1163 ◽  
Author(s):  
Zhuo Wang ◽  
Michael T. Montgomery ◽  
Cody Fritz
Keyword(s):  
Tropical Cyclone ◽  
Large Scale ◽  
Deep Convection ◽  
Vertical Shear ◽  
Recirculation Region ◽  
Necessary Condition ◽  
Tropical Cyclogenesis ◽  
Sufficient Condition ◽  
Easterly Waves ◽  
Tropical Cyclone Formation

In support of the National Science Foundation Pre-Depression Investigation of Cloud-systems in the tropics (NSF PREDICT) and National Aeronautics and Space Administration Genesis and Rapid Intensification Processes (NASA GRIP) dry run exercises and National Oceanic and Atmospheric Administration Hurricane Intensity Forecast Experiment (NOAA IFEX) during the 2009 hurricane season, a real-time wave-tracking algorithm and corresponding diagnostic analyses based on a recently proposed tropical cyclogenesis model were applied to tropical easterly waves over the Atlantic. The model emphasizes the importance of a Lagrangian recirculation region within a tropical-wave critical layer (the so-called pouch), where persistent deep convection and vorticity aggregation as well as column moistening are favored for tropical cyclogenesis. Distinct scenarios of hybrid wave–vortex evolution are highlighted. It was found that easterly waves without a pouch or with a shallow pouch did not develop. Although not all waves with a deep pouch developed into a tropical storm, a deep wave pouch had formed prior to genesis for all 16 named storms originating from monochromatic easterly waves during the 2008 and 2009 seasons. On the other hand, the diagnosis of two nondeveloping waves with a deep pouch suggests that strong vertical shear or dry air intrusion at the middle–upper levels (where a wave pouch was absent) can disrupt deep convection and suppress storm development. To sum up, this study suggests that a deep wave pouch extending from the midtroposphere (~600–700 hPa) down to the boundary layer is a necessary condition for tropical cyclone formation within an easterly wave. It is hypothesized also that a deep wave pouch together with other large-scale favorable conditions provides a sufficient condition for sustained convection and tropical cyclone formation. This hypothesized sufficient condition requires further testing and will be pursued in future work.

scholarly journals The Winter Habitat Selection of Red Deer (Cervus elaphus) Based on a Multi-Scale Model

Animals ◽  
2020 ◽  
Vol 10 (12) ◽  
pp. 2454
Author(s):  
Yue Sun ◽  
Yanze Yu ◽  
Jinhao Guo ◽  
Minghai Zhang
Keyword(s):  
Habitat Selection ◽  
Environmental Factors ◽  
Cervus Elaphus ◽  
Red Deer ◽  
Scale Model ◽  
Winter Habitat ◽  
Multi Scale ◽  
Optimal Scale ◽  
Scale Models ◽  
Selection Of

Single-scale frameworks are often used to analyze the habitat selections of species. Research on habitat selection can be significantly improved using multi-scale models that enable greater in-depth analyses of the scale dependence between species and specific environmental factors. In this study, the winter habitat selection of red deer in the Gogostaihanwula Nature Reserve, Inner Mongolia, was studied using a multi-scale model. Each selected covariate was included in multi-scale models at their “characteristic scale”, and we used an all subsets approach and model selection framework to assess habitat selection. The results showed that: (1) Univariate logistic regression analysis showed that the response scale of red deer to environmental factors was different among different covariate. The optimal scale of the single covariate was 800–3200 m, slope (SLP), altitude (ELE), and ratio of deciduous broad-leaved forests were 800 m in large scale, except that the farmland ratio was 200 m in fine scale. The optimal scale of road density and grassland ratio is both 1600 m, and the optimal scale of net forest production capacity is 3200 m; (2) distance to forest edges, distance to cement roads, distance to villages, altitude, distance to all road, and slope of the region were the most important factors affecting winter habitat selection. The outcomes of this study indicate that future studies on the effectiveness of habitat selections will benefit from multi-scale models. In addition to increasing interpretive and predictive capabilities, multi-scale habitat selection models enhance our understanding of how species respond to their environments and contribute to the formulation of effective conservation and management strategies for ungulata.

scholarly journals Anchoring Multi-Scale Models to Micron-Scale Imaging of Multiphase Flow in Rocks

2021 ◽  
Author(s):  
Shan Wang ◽  
Leonardo C. Ruspini ◽  
Paal-Eric Oeren ◽  
Stefanie Van Offenwert ◽  
Tom Bultreys
Keyword(s):  
Multiphase Flow ◽  
Multi Scale ◽  
Scale Models

scholarly journals Macroscopic and Multi-Scale Models for Multi-Class Vehicular Dynamics with Uneven Space Occupancy: A Case Study

Axioms ◽  
2021 ◽  
Vol 10 (2) ◽  
pp. 102
Author(s):  
Maya Briani ◽  
Emiliano Cristiani ◽  
Paolo Ranut
Keyword(s):  
Road Network ◽  
Real Data ◽  
Second Order ◽  
Heavy Vehicles ◽  
First Order ◽  
Multi Scale ◽  
Stop And Go ◽  
Scale Models ◽  
Road Space

In this paper, we propose two models describing the dynamics of heavy and light vehicles on a road network, taking into account the interactions between the two classes. The models are tailored for two-lane highways where heavy vehicles cannot overtake. This means that heavy vehicles cannot saturate the whole road space, while light vehicles can. In these conditions, the creeping phenomenon can appear, i.e., one class of vehicles can proceed even if the other class has reached the maximal density. The first model we propose couples two first-order macroscopic LWR models, while the second model couples a second-order microscopic follow-the-leader model with a first-order macroscopic LWR model. Numerical results show that both models are able to catch some second-order (inertial) phenomena such as stop and go waves. Models are calibrated by means of real data measured by fixed sensors placed along the A4 Italian highway Trieste–Venice and its branches, provided by Autovie Venete S.p.A.

scholarly journals In-Station Train Movements Prediction: from Shallow to Deep Multi Scale Models

2021 ◽  
Author(s):  
Gianluca Boleto ◽  
Luca Oneto ◽  
Matteo Cardellini ◽  
Marco Maratea ◽  
Mauro Vallati ◽  
...  
Keyword(s):  
Multi Scale ◽  
Scale Models

scholarly journals Systematic Integration of Structural and Functional Data into Multi-Scale Models of Mouse Primary Visual Cortex

2019 ◽  
Author(s):  
Yazan N. Billeh ◽  
Binghuang Cai ◽  
Sergey L. Gratiy ◽  
Kael Dai ◽  
Ramakrishnan Iyer ◽  
...  
Keyword(s):  
Visual Cortex ◽  
Primary Visual Cortex ◽  
Functional Data ◽  
Multi Scale ◽  
Scale Models

scholarly journals The Development of Multi-scale Data Management for CityGML-based 3D Buildings

2021 ◽  
Vol 16 (1) ◽  
pp. 71-94
Author(s):  
Hairi Karim ◽  
Alias Abdul Rahman ◽  
Suhaibah Azri ◽  
Zurairah Halim
Keyword(s):  
City Development ◽  
Multi Scale ◽  
Levels Of Detail ◽  
Current Implementation ◽  
Single Scale ◽  
Spatial Management ◽  
Scale Models ◽  
Efficient Information ◽  
Control And Management ◽  
Multi Scales

The CityGML model is now the norm for smart city or digital twin city development for better planning, management, risk-related modelling and other applications. CityGML comes with five levels of detail (LoD), mainly constructed from point cloud measurements and images of several systems, resulting in a variety of accuracies and detailed models. The LoDs, also known as pre-defined multi-scale models, require large storage-memory-graphic consumption compared to single scale models. Furthermore, these multi-scales have redundancy in geometries, attributes, are costly in terms of time and workload in updating tasks, and are difficult to view in a single viewer. It is essential for data owners to engage with a suitable multi-scale spatial management solution in minimizes the drawbacks of the current implementation. The proper construction, control and management of multi-scale models are needed to encourage and expedite data sharing among data owners, agencies, stakeholders and public users for efficient information retrieval and analyses. This paper discusses the construction of the CityGML model with different LoDs using several datasets. A scale unique ID is introduced to connect all respective LoDs for cross-LoD information queries within a single viewer. The paper also highlights the benefits of intermediate outputs and limitations of the proposed solution, as well as suggestions for the future.

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